Two of the world’s largest carbon dioxide pipelines are set to pass through Minnesota, carrying the climate-poisoning gas to burry it deep underground – while also falling into a regulatory black hole.
CO2 is considered a hazardous pipeline fluid under federal law and in some states, including Iowa, but not Minnesota.
The pipelines — one of which would be more expensive than Enbridge’s pipeline project in northern Minnesota — would primarily transport CO2 captured from ethanol plants in the Midwest.
Transport and storage of CO2 have never been done on this scale. Carbon capture technology is still in its infancy. And a 2020 pipeline accident in Mississippi prompted an evacuation and injured dozens.
“CO2 is a hazardous material that can lead to absolutely disastrous ruptures,” said Bill Caram, executive director of the Pipeline Safety Trust, a group based in Washington state. Although CO2 is not explosive like natural gas, it is an asphyxiant that can be fatal in large doses.
Currently, CO2 pipelines do not require Minnesota Public Utilities Commission (PUC) approval. But the PUC opened a case in December on whether it should change state regulations to deem CO2 pipelines unsafe. The Minnesota Departments of Transportation, Agriculture, Commerce, and Natural Resources (DNR) all support such a change.
“A growing body of research has raised concerns about the safety and environmental effects of pipelines carrying CO2,” the DNR said in a PUC filing on Monday. “Pipeline leaks or ruptures can cause CO2 to build up in low-lying areas [including basements of area residences and building]thereby displacing oxygen.”
The Midwest Carbon Express, offered by Ames, Iowa-based Summit Carbon Solutions, would travel 150 miles in Minnesota, connecting to five ethanol plants. The Heartland Greenway, proposed by Texas-based Navigator CO2 Ventures, would run 12 miles through Minnesota, connecting to an ethanol plant.
Both pipelines are huge financial outlays: At $4.5 billion, the Summit pipeline would cost nearly $500 million more than the U.S. portion of Enbridge’s new Line 3 pipeline (most of which is in Minnesota). The Navigator project would cost around $3 billion.
Deep-pocketed private equity investors are behind both projects, hit by federal “45Q” tax credits. The credit, which will provide $50 per ton of carbon captured and sequestered, is potentially worth billions of dollars to Summit alone.
“There’s no economic incentive without 45Q to store CO2,” said Jessie Stolark, public policy manager for the Carbon Capture Coalition, a pro-carbon capture group created by the Carbon Capture Research Group. Minneapolis-based nonprofit energy, the Great Plains Institute.
Pipelines could help ethanol market
Carbon capture has become an increasingly popular – though often controversial – concept in recent years. It aims to reduce greenhouse gas emissions, the cause of climate change.
Plans abound to refurbish fossil fuel power generators to capture and store carbon CO2, especially in North Dakota. But so far, carbon capture from coal has worked poorly.
Ethanol plants are major sources of CO2. Their carbon capture is considerably cheaper than in coal-fired power plants. The latter requires expensive equipment to remove impurities from burning coal. The CO2 from ethanol – a byproduct of corn fermentation – is cleaner.
“What makes ethanol plants such a good target is that you have almost pure CO2,” said Chris Hill, Summit Carbon Solutions’ director of environment and permits.
Besides Minnesota, the Summit pipeline would collect CO2 from ethanol plants in Iowa, Nebraska and the Dakotas. The company aims to ship 12 million tons of liquefied CO2 annually to North Dakota where it would be stored more than a mile underground.
“We’re at the forefront of building infrastructure like this,” Hill said.
Navigator CO2 Ventures’ multi-state pipeline would connect to about 20 ethanol plants, including one just west of Fairmont, Minnesota. The pipeline would end in Illinois, which, like North Dakota, has geology conducive to deep CO2 storage.
In Iowa, where the two pipelines are furthest along in permitting, opposition has arisen from landowners and environmental groups.
Carbon capture has the potential to make ethanol makers – which have been beaten economically in recent years – more profitable.
“I think it definitely secures our future,” said Brian Kletscher, CEO of Highwater Ethanol in Lamberton, Minnesota, which would connect to the Summit pipeline. “The dollar value comes from the decline in our carbon intensity score.”
This score measures the amount of carbon dioxide emitted relative to the transportation energy supplied. By capturing its CO2, an ethanol plant can cut its score in half, Kletscher said.
With the lowest score, he said producers like Highwater can get a premium for their ethanol in California, Oregon and Washington, all of which have imposed clean fuel laws. Several other states, including Minnesota, are also considering such laws, as is Canada’s federal government.
By capturing carbon, ethanol manufacturers can also sell credits to companies looking to lower their carbon intensity profiles.
Summit will own and operate CO2 capture equipment at Highwater and other ethanol plants. The pipeline operator will receive about half of the Clean Fuel Bonus, Summit’s main source of revenue. Additionally, a significant portion of Summit’s revenue would come from 45Q tax credits, Hill said.
Federal tax credits for storage are crucial because the market for CO2 is so limited. Oil companies are the main consumers of carbon dioxide, buying it from pipelines and injecting it into depleted wells to extract the remaining oil.
CO2 can cause disease
There are approximately 5,000 miles of carbon dioxide pipelines in the United States – a fraction of the country’s 2.6 million miles of natural gas, oil and petroleum products pipelines.
The worst accident on the CO2 line appears to have occurred in 2020 near Satartia, Mississippi. A 24-inch pipeline belonging to an oil and gas company ruptured, leading to the evacuation of more than 300 people. Forty-six were treated for injuries at local hospitals.
Law enforcement officers told the Jackson (Miss.) Clarion Ledger that some people overwhelmed by gas walked around like “zombies” while others were “foaming at the mouth.”
The Mississippi rupture also released hydrogen sulfide, a dangerous gas that often lurks in natural CO2 deposits. However, it would not be present in the purer CO2 stream from ethanol plants, according to Summit and Navigator. Also, the diameter of CO2 pipes in Minnesota would be relatively small – mostly 6 to 8 inches.
Yet CO2 leaks alone can cause difficulty breathing, rapid heartbeat, vomiting, headaches and impaired thinking. The Great Plains Institute said in a PUC filing that there have been no fatalities in the history of CO2 pipeline operations. But death by suffocation is possible if CO2 concentrations are high enough, including for wildlife and livestock near a pipeline rupture.
The CO2 circulating in the pipes is put under pressure. It has the density of a liquid and the viscosity of a gas – two good characteristics for transportation. But during a rupture, CO2 quickly depressurizes and reverts to a pure gaseous phase, increasing the risk of “ductile fractures”, said Caram of the Pipeline Safety Trust.
“If there’s a ductile fracture, it can tear the line like a zipper and it can be miles long,” he said.
Gas pipelines are mainly supervised by the federal government. In Minnesota, the PUC issues permits for pipelines carrying hazardous liquids, including petroleum, petroleum products, and ammonia.
The PUC sent comments on whether to include carbon dioxide on this list. For now, C02 pipelines would only need county permits.
The PUC acted shortly after Minnesota-based Clean Up the Riverfront Environment (CURE) requested a state environmental review of CO2 pipelines. CURE says an “environmental assessment spreadsheet” is required by law.
Both pipeline companies have since said they would voluntarily proceed with the assessment. But both object to the PUC deeming CO2 a dangerous liquid for their pipelines.
Along with branches of Gov. Tim Walz’s administration, the Upper Sioux community, two labor unions, CURE and several citizens have filed comments with the PUC calling for CO2 pipelines to be regulated as unsafe.
“The commission adopted its definition of a hazardous liquid in 1988, when [carbon capture] the technology was still relatively unknown outside of oil-rich states like Texas,” CURE said in a PUC filing.
Yet CO2 is “precisely the type of dangerous liquid envisioned by lawmakers” in the 1980s.